Drilling machine spindle



July 11, 1933. A M JOHNSON I 1,917,842

Filed Oct. 10. 1929 Patented July 1l, 1933 STATE Meer esta ALBERT M. JOHNSON, or nooKFoRn, ILLINOIS, .assGNoa are ,Brianna narrar COMPANY,

or nocnroian, rLLrNos, .a oonronarroia or inrrNors r .f

. v DRILLrNG MAcHrNn srrNnrln origami application med october 10,1929, serial No. 393,709. Divided and l 1931. Serial No. 525,715.

The inveiition-relates to spindle structures for drilling machinesand the like, in which the spindle proper is mounted for rotation in a nonaotatable sleeve through the medium of which the drill or other cutting tool is fed to the work.

In the case of prior spindle structures of the character referred to it has been cus toinaryin the construction of the parts to em-V ploy a relatively soft steel such as would permit of proper machining; and as an incident to this characteristic of the metal, separately formed and hardened raceways have been employed between opposite ends of the spindle and the sleeve.

These prior spindle structures have been subject to the objection that due tothe use of such relatively soft metal, they do not possess sul'hcient strength and rigidity tol withstand the extreme pressures and resultant bending strains to which they are in some instances subjected, as in the case of hydraulic drill presses; and moreover they do not properly resist wear. It has thus been necessar f fre uentl to re Jair and to replace dam-l .l Y

aged spindle units.

The object of the present invention is to provide a novel. spindle structure such that it shall possess substantially greater strength than prior spindle structures and greater wear resisting qualities than has been possible to obtain heretofore.

In the accompanying drawing wherein l have shown a preferred embodiment lof my invention Figure l is a fragmentary side elevational view of a spindle structure with parts broken away to show details of construction.

Fig. 9, is a plan view of the structure shown in Fig. l but on a. larger scale.

Fig. 3 is a transverse sectional view takenv approximately in the plane of line 3 5 of Fig. l and'also on a larger scale.

ln the spindle structure shown, 10 designates the spindle proper with splined grooves 1l at its upper end for driving purposes, and having at its lower end the usual drill chuck 1Q. The latter has the customary taper socket 13 and a transverse drift pin holel ll at the upper end of the socket. p

parts a special alloy steel this appncmibn nea March 27,

if) designates the spindle sleeve held against longitudinal movement relativeto the spindle in any preferred manner. As shown, y

'a collar 16 is threaded onto the spindle above the sleeve with a washer 1'4" interposed be-'55 tween' it and the sleeve. Between the lower end of the sleeve and the Vchuck l2 is interposed a thrust bearing 18 of suitable character. A feeding rack 19 is, as shown, formed integral with the sleeve at one.sidethei'eoffe grooves lea being formed .at opposite sides of this rack to receive guide rollers (not shown) which serve to hold the sleeve against rotation when mounted in the machine.

ln order tolend greater strength tothe 65 spindle structure and to' increase its durability, l employ; a mode of manufacture in which the spindle and sleeve` are lirst machined andv then hardened by means of a suitable non-wai'ping process so that the spindle 70 unit possesses not only much greater strength and 4rigidity than prior spindle units, 'but also much higher wear resisting qualities. llhus, l preferably employ in both of said,

suoli, for example, '75 as that known to the trade asv Nitralloy, and after the parts are properlymachined I subject them to the action of ammonia gas under low temperatures, a process known as the nitridingprocess.

rlhe use of a relatively costly alloy steel and special hardening process in place of the more ordinary materials and process heretofore used would, with the construction and arrangement heretofore employed, be practical- 85 ly prohibitivefrom the standpoint of cost .of manufacture. lhave overcome this dif- Vbeen able to reduce the diameter of the sleeve .than the diameter of the spindle, andeach end of the sleeve is counterbored toform an annular groove providing the outer racevvay 20. lVithin this groove is inserted a cage 2l which is in the form of a ring provided with sockets at spaced points to receive roller bearings'QQ which engage throughout their lengthswith the outer raceway and hence provide a large bearing surface., The inner raceway with Which said rollers coact is formed directly on the spindle, preferably on a somewhat enlargedVv cylindrical portion 23, the rollers being of'ay diameter slightly greater than the thickness ofthe ring forming the cage. rl`he upper. bearingris held in position inthe'sleeve by meansofr-the nut and Washer 16, 1 7, and thelowerbearing is retained vby the antifriction thrust bearing l8.

ItWill-Abe seen that Ihave provided a spindle strncturepossessing substantially greater Y strength andrigidity as Well as greater durability, thanprior structures, and that l havel accomplished this result by a construction and arrangement which, through the elimination of parts necessarily employed in prior-straw tures, and by a substantial reduction in the amountof material necessary to be employed is not rendered impracticable on account of the use of special materials or processes.A

Moreover, by reason of the fact that all machining operations may be completed before heat treating, the cost of manufacture is re- Y the case,

This application is a division of my copending application Serial No. 398,709, iiled October l0, 1929.

l claim as my invention :V

`A spindle structure for drilling machines and the like comprising a spindle, a sleeve having air .internal diameter' 'only slightly greater than the spindle, means on the Aspindle coacting With opposite ends of the sleeve to hold it against longitudinal movement but permitting relative rotation, saidV sleevehaving a pair of internal annular grooves respectively formed at opposite ends, and roller bearings held in circumferentially spaced relation in said grooves and bearing directly against the peripheral Walls of the grooves and against'the adjacent peripheral surfaces on the spindle, said spindle and sleeve being made of analloy steel hardened throughout their lengths by a non-warping process such as nitridinfr. y y

-n testimony whereof, I have hereunto af- `fixed'my signature. 1

ALBERT M. JOHNSON, 

